Phase 1 of the 160m vertical project is underway… and as usual, it didn’t quite go to plan! In this episode, we:
– Lay the main mast down and test-fit a 9m extension (Signature 9 pole)
– Work out how to physically clear the surrounding trees (with a bit of improvisation!)
– Start thinking about the loading coil approach for a shortened 160m vertical
– Look at how the existing ground system (from the 40m 4-square) might be reused
– Discover some interesting behaviour in the mast under wind load…
There’s a mix of practical field work, a bit of problem solving, and yes… some questionable tree surgery decisions along the way. Technical highlights:
– ~19m existing mast used as a base for a shortened 160m vertical
– Planned loading coil (~30 turns on 4” former) to compensate for missing length
– Shared radial field (~800m of wire already in the ground)
– Top-loading effects from existing Yagis (unexpected bonus!)
– Early testing reveals guy rope stretch issues → likely move to Dyneema
This is very much an experiment in progress – real-world antenna building, not textbook perfection.
If you’ve ever wondered: Can you get away with a short 160m vertical? How much does top-loading really help? What actually happens when a mast starts bending in the wind? …then this one’s for you.
Next steps:
– Swap guy lines to low-stretch Dyneema
– Decide: taller mast vs loaded vertical
– Finalise coil tap points and feed arrangement
73, Callum.
